Electric hand lamp



. March 31, 1936.

o. JANZEN 2,035,812

ELECTRIC HAND LAMP Filed Dec. 12, 1934 Illlllllll J22 vezzior:

, the invention, 40

him have been pressed Patented Mar. 31', 1936 UNITED STATES. PATENTOFFICE E ili -3:1,, OttoJanzcmBcflImGermany Application December 121934. Serial No. 151,205 In Germany December 15, 1933 4 claim. (01.240-105) toothed wheel into a movement of rotation of the dynamo. Insuch hand lamps the rotor has had a very high speed of rotation,particularly when the rotor has formed the magnet, with the inducedwinding arranged on the stator, With these dynamos, which are generallyfour-pole machines, either a very frequent or a powerful pressure hashad to be' exerted on the operating lever in order to obtain thenecessary Lwattage output, which has been Hand .lamps have also beenproposed wherein the various compone is of the internal mechainto thetwo halves of an outer casing made of insulating material,

the two halves ofthe casing being provided with a screw-thread by meansof which they are assembled together. In this case, however, there hasbeen the disadvantage that any inaccuracies or defects caused in theinternal mechanism during the assembling of the parts or subsequently,cannot be remedied. In dynamos used for hand lamps and driven by leverpressure, it has also already been proposed to retain the pressure leverin the position of rest by means of a locking device or the like.

The present invention has for its object to provide an improvedconstruction of hand lamp operating by means of a small dynamo whereinthe above disadvantages are overcome. In a constructipn of hand lampaccording to the lamp comprises a small twopole dynamo which is formedas a unit independent of the lamp casing. According to a feature of theinventio {the said dynamo unit is resiliently mounted'in the lampcasing. Preferably, the unit is only connected to the by means of itsshaft, so that it is pivoted about this shaft. By means of thisconstruction, cthe transmission -of the noise of the machine or of thedriving mechanism to the exterior isreduced and any irregularities inmanuthe dynamo and casare also compensated for.

facture, such as between .I'he dynamo may be set in rotation by means apower lever operated by hand and preferably comprises a'tw -pole magnetas rotor, so as to obtain maximum steel masses for the pole pieces ifound inconvenient in using the lamp for a long period at a time.

' wattage output can be obtained.

' which is described hereafter,

as an independent unit.

which are required for electro-magnetic sons, which pole pieces, as iswell-known, each extend preferably over a quarter of the circumferenceof the rotor. This two-pole bar-shaped rotor is completed to form acircular mass by 5 means of a heavy non-magnetic metal, whereby airresistances are avoided in the dynamo and the centrifugal mass of therotor is substantially increased; In order to obtain a permanentconnection between the magnetic and the nonmagnetic parts of the rotor,the heavy metal mass is so aiilxed to the magnetic part, preferably bymeans of the spray casting process, that the bar-shaped magnet isembedded in the heavy metal without the latter forming a short-cirl5cuit. The'construction of the dynamo as a twopolemachine' with arotating magnet armature also permits a relatively large amount ofirontobeusedforthestatorinthesmallspace available, so that even at low Thelow speed in turn otters the advantage that only a fewgear wheels arerequired for the transmission. between the operating lever and the rotorof the dynamo, and these wheels maytherefore be of powerful fconstruction, whereby a comparatively small force is sufficient to drivethe dynamo.

The invention will bejmore clearly understood from the particularembodiment thereof by way of example, with reference to the accompanyingdrawing, in which:

Figs. 1 and 2 represent, in a partial section in front and, side viewsrespectively, the dynamo a sectionthrough dynamo inserted in the Fig. 3is a side elevation of the casing, showing the casing Fig 4 is a frontview of the dynamo inserted 4m in the casing, with half of the casingremoved.

. The two-pole stator i, preferably of laminated iron, carries on itsyoke the induced winding 2 and on its faces the bearing bracket 3 forthe rotor I, which is formed as a two-pole bar magnet and is completedby a heavy non-mag-f .netic metal M5, to form a completely circulardisc. This non-magnetic metal is sprayed round the magnetic barin sucha. manner that it completely surrounds the latter on three sides, whileleaving the pole pie'ces free, but penetrates on one of the flat sidesinto dovetail-like recesses i in the'rotor 4, whereby a. firm connectionis obtained in the radial direction whilst avoiding a shortcircuit.A'gear wheel 1 is fixed on the" shaft of sne da z eo rubber tube ofsuitable length.

As shown in Figs. 3 and 4, the lamp casing comprises two halves M madefrom press-ed insulating material, a bulb it being, provided in theusual way, having means it and H for connection to the winding 2. Thesingle-armed operating lever lil is pivotally mounted on the axis id inone of the halves oi the casing. The am's it automatically movesoutwards under the action of the spring 29, and the lever 58 is providedat its end with an arcuate rack it which meshes with the driving wheel12 of the dynamo. In the rack 2!, is provided a recess 22 in whichengages a pawl 23 which when pressure is exerted on the lever H8 in theposition of rest, releases this lever under pressure of the spring 2%,and is provided with a locking memher (not shown) passing through thecasing.

The connection of the dynamo to the casing is merely efiected throughthe-driving shaft Q which may be constructed either directly as aconnecting screw for the two halves of the casing or as a hollow shaftthrough which passes a connecting screw. Further connecting screws orthe like for the casing may be provided, for

instance, in the shalt It or at the point 25 at the upper end of thelamp. 1% shown in Fig. 3, the hollow shaft 9 may be threaded to" engagethe threads of a member such as e which extends through the casing. Onesuch screw 9' may be provided on each side and these will serve to holdthe two halves of the.

casing assembled with relation to the contained mechanism. Owing to theabove construction, the dynamo is pivotally mounted on the axis 9 withinthe casing and is resiliently held therein by the rubber lining l3.Substantially circular recesses may be provided in the two halves of theat the bottom, into which recesses are pressed parts of the rubberlining during assemblage, so as to prevent any swinging movement of thedynamo. This may also be assisted byprojections 26 provided on-thenarrow sides of the casing. Any inequalities in the depth of the twohalves or the casing or inthe overall height of the dynamo arecompensated by the resilient mounting of the latterinfa manner whichsubstantially simplifies the assemblage of thewhole. a

l br operation of the handlamp, the lever l8, which is locked by hand inthe position of rest by means of the pawl 23, is pressed slightly harderthan usual against the casing ll, so as to unlock it under the action ofspring 2!, and

the level then springs outwards under the action of spring 20. Bypressing the lever l8 down again against the casing, the rotor of thedynamo is set in movement by means of the rack 2| which connected to thelever i8 and through the wheel l2, coupling ll andv I gear wheels 8 andI to the rotor. The necessary wattage output is'thus obtained to operatethe lamp fromthe dynamm. When the pressure on thalcver I 8 ceases thelever is again moved outforce is not reduced.

aoeaeia wards by the spring 20, the driving wheel I! of the dynamoreversing; since, however, the coupling l l is inactive in thisdirection, the further rotation of the rotorgxaused by centrifugal 1. Inan electric hand lamp, the combination of a lamp casing, said-casinghaving a removable portion, a hand-operated two-pole dynamo mountedtherein and formed as a unit independ- 'ent of said casing, said dynamounit including a stator having an induced winding, a rotor comprising atwo-pole bar magnet and a member of heavy non-magnetic material edthereto and forming with said magnet a substantially circular mass, andadriving shaft for said rotor, said driving shaft coacting with saidcasing. to pivotally mount said dynamo unit therein and serving also asa means for holding the two portions of said casing together whenassembled, and resilient means for positioning said dynamo unit in saidcasing.

2. In an electric hand lamp, the combination of a lamp casing, saidcasing having a. removable portion, and a hand-operated two-pole dynamomounted therein and formed as a unit independent or said casing, .said 0unit including a stator having an induced winding and a rotor comprisinga two-pole bar magnet and a member oi heavy non-magnetic material amxedthereto and forming with said magnet a substantially circular mass, abracket on said stator for carrying said rotor, and a driving shaft forsaid rotor, said driving shaft coacting with independent of said casing,said dynamo unit including a stator havingan induced winding, a rotorcomprising a two-pole bar magnet and a member of heavy non-magneticmaterial atfixed thereto and forming with said magnet a substantiallycircular mass, and means for driving saidrotor comprising a drivingshaft, a first gear wheel mounted on said driving shait,and

. a second gear wheelialso mounted on said shaft and coupled to saidfirst wheel by a coupling member operative only in one direction orrota-' tion of said shaft, resilient means forpositioningsaiddynamounitinsaidcasingaspring controlled hand lever onsaid casing, and means including an arcuate rack coactingwith secondgear wheel of said dynamo unitand operated by said hand lever,Ior'converting the movement of said hand lever-into a movement ofrotation of said rotor or said dynamo unit.

4. In an electric hand lamp, the combination.

of a lanip casing, said casing having a removable portion, a'hand-operated two-pole dynamo mounted therein and formed asa unitindependent of said casing, said dynamo unit in cluding a statoroflaminate'dlron carrying an induced winding and a rotor comprising atwopole bar magnet and a member of heavy nonmagnetic material afllxedthereto and forming with said magnet a substantially circular mass, abracket on said stator for carrying said rotor, a facing of resilientmaterial on the outer faces of said bracket which coact with theinternal walls of said casing 'to position said dynamo .unit therein, adriving shaft for said rotor, said driving shaft coacting with saidcasing to pivotally mount said dynamo therein and serving also as ameans for holding the two portions of said casing together whenassembled, a first gear wheel mounted \on said driving shaft, and a ,3second gear wheel also and coupled to said first wheel by a. couplingmember operative only in one direction of rotation of said shaft, aspring-controlled hand lever on said casing, means including an arcuaterack coacting with said second gear wheel of said dynamo unit andoperated'by said hand lever, for converting the movement of said handlever into a movement of rotation of said rotor of said dynamo unit, anda spring-controlled stop member for locking said hand lever in theposition of rest.

O'I'IO JANZEN.

mounted on said shaft-

